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Substatus, Limit, Table 4-8. limit values – National Instruments FP-3000 User Manual

Page 74: Mode_blk parameter and mode handling, Target mode, Substatus -22 limit -22, Mode_blk parameter and mode handling -22, Target mode -22

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Chapter 4

Block Reference

FieldPoint FP-3000 User Manual

4-22

www.ni.com

Substatus

The

Substatus

field is used to describe more specifically the cause of the

given quality. For example, a status with the quality of

Bad

might have a

substatus of

Device Failure

, indicating that the value should not be

trusted because it is from a device that has failed. Another common
substatus is

Non-specific

. The

Non-specific

substatus is used when

no other substatus applies. There are numerous substatuses.

Limit

Table 4-8 describes the

Limit

subfield values.

MODE_BLK Parameter and Mode Handling

The block’s mode behavior is controlled with the

MODE_BLK

parameter.

The

MODE_BLK

parameter contains four fields that allow the current mode

of the block to be read and the desired mode for the block to be written.
The four fields are

TARGET

mode,

ACTUAL

mode,

PERMITTED

mode, and

NORMAL

mode.

TARGET Mode

The desired mode of execution for the block. An operator or process
engineer normally writes this to put the block in the desired mode of
operation.

Table 4-8. Limit Values

Value

Meaning

None

The value is not limited.

Low

The value is at a lower limit. This can be caused by
a transducer limitation or setpoint limits.

High

The value is at a high limit. This can be caused by
a transducer limitation or setpoint limits.

Constant

The value is at a fixed value and cannot move. This
results from the block supplying the value being in
manual mode.